Neoplasm of uncertain behavior of unspecified kidney

This code signifies a renal mass or lesion that has been identified but whose biological behavior (benign vs. malignant) cannot be definitively determined from the available pathological or clinical information. It represents an ambiguous neoplastic process originating in the kidney, where further investigation is typically warranted.

Assign this code when pathology reports or imaging studies describe a kidney neoplasm as "uncertain behavior," "borderline malignancy," or "indeterminate." It is appropriate when the documentation explicitly states that the tumor's nature cannot be classified as either benign or malignant.

• Do not use this code if the documentation specifies the neoplasm as benign (e.g., adenoma) or malignant (e.g., renal cell carcinoma).
• Ensure the documentation clearly links the uncertain behavior to the kidney; avoid using this code for unspecified sites.
• If a definitive diagnosis is later established, update the code to reflect the confirmed benign or malignant nature of the neoplasm.